Bone and Joint Part 2. Leslie G Dodd, MD

Transcription

1 Bone and Joint Part 2 Leslie G Dodd, MD

2 Relative rates of cancer Sarcomas are relatively uncommon tumors New cancer cases 2007 All sites 1.4 million prostate 218,890 lung 213,380 breast 180,510 Soft tissue 9,220 Bone 2,370 Jenal A, Siegel R, Ward E et al. Cancer Statistics, CA Cancer J Clin 2007:57:43-66

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5 Bone tumor classification Osseous lesions benign malignant Cartilage forming lesions benign malignant Other Fibrous Cyst Giant cell tumor Round cell Metastases P jpg

6 Osteoid Osteoma Clinical: Pain of increasing severity; worse at night and relieved by aspirin referred pain to joints; scoliosis, muscle atrophy and neurological disorder Diaphysis/metaphysis of long bones and appendicular skeleton

7 Osteoid Osteoma Radiology: small lucency, surrounded by sclerosis and cortical reaction At center of lucency is a nidus---small area of ossification lesion is easily missed on conventional exam; may require tomo or CT Ddx: Brodie s abscess, stress fracture or osteoblastoma

8 Osteoid osteoma Peripheral bone sclerotic Inner nidus

9 Osteoblastoma Radiology: may simulate osteoid osteoma but can be highly variable in appearance Can be destructive and confused for malignant process Central ossification is common

10 Osteoblastoma Histopathology: Similar to osteoid osteoma although not as well organized Tends to be highly vascular in central portion

11 Osteosarcoma Clinical: Pain and tender mass of relatively short duration Knee is most common site **Aggressive treatment approach with neoadjuvant chemotherapy and limb salvage Early development of pulmonary mets Predisposing conditions: Pagets and Radiation

12 Large peak in children/young adults. Small peak in later years. Most frequently affected site is in the metaphysial area in long bones, but can happen elsewhere.

13 Osteosarcoma Radiology: metaphyseal lesion which can be mixed lytic and blastic Poorly delineated; cortical destruction with soft tissue extension Spiculation and Codman s triangle MRI/CT to define extent of intramedullary spread

14 Osteosarcoma

15 Osteosarcoma

16 Osteosarcoma Histopathology: Highly variable with osteoid, chondroid or fibrous matrix predominant All have in common the production of tumor osteoid and malignant osteoblasts Spindled sarcomatous stromal element with anaplasia and mitotic figures Foci of degeneration, infarction or heavy osteoid formation with sclerosis Lace-like osteoid pattern is common

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18 Osteosarcoma--- conventional

19 Osteoid

20 Treatment Amputation produced 20% 5 yr DFS Neo-adjuvant chemotherapy plus surgery results in 60-65% 5 yr DFS Limb salvage surgery appropriate in 80% of cases

21 Chondroid tumors Osteochondroma Enchondroma Chondroblastoma Chondromyxoid fibroma Chondrosarcoma

22 Osteochondroma Clinical: Obvious mass lesion; often of long duration Not painful unless impinges on a structure (bursa) Risk of chondrosarcomatous degeneration Hereditary multiple exostoses syndrome

23 Favored site for osteochondromas

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25 Enchondroma Clinical: Common benign lesion; asymptomatic, painless and incidentally discovered Grow up to 3 cm; mass lesion in hands and feet Peripheral skeleton is common (Vs. central for chondrosarcoma) Up to 10% of all bone tumors Multiple enchondromas associated with Ollier s and Maffuci s syndromes

26 Enchondroma-Radiology Variable intralesional calcification Rings and arcs pattern in long bone have metaphyseal location and can simulate a bone infarct

27 Enchondroma Histopathology: Circumscribed, lobulated lesion comprised of lobules of cartilage separated by thin septae micro appearance of benign cartilage

28 Enchondroma Peripheral concentration of chondrocytes Minimal cytologic atypia (digits); may have bi-nucleate chondrocytes Focal calcification and enchondral ossification

29 Multiple enchondromas- Ollier s and Maffucci s Ollier s disease Maffuci s disease hemangiomas

30 Chondroblastoma Clinical: Less than 1% of all bone tumors In young individuals with open epiphyses Pain in affected region May have corresponding joint effusion Most common site is distal femur/proximal tibia

31 Chondroblastoma Radiologic: Located in epiphyses of long bones in skeletally immature individuals Sharply demarcated oval/round lesion surrounded by sclerotic bone Typically does not alter bone contour unless accompanied by ABC (20%) May have fine to course intralesional calcification

32 Chondroblastoma Histopathology: Chondroblasts, characterized by small cells with high N/C ratio and clefted nuclei Variable mature or immature cartilaginous matrix Chicken-wire calcification pattern associated with blastic foci Few multinucleate giant cells

33 Chondromyxoid fibroma Extremely rare lesion (< 1%) with wide age range Most common location is knee; proximal tibia accounts for 25% of all may present with tenderness or swelling but is often an incidental finding

34 Chondromyxoid fibroma Radiologic: Eccentric, metaphyseal lytic defect Long axis of lesion parallels long axis of affected bone Sharp, sclerotic and scalloped margins; may be lobulated or septated Typically lacks intralesional calcification

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36 Chondrosarcoma Clinical: Wide age range; tumor in adults is most common; predisposing factors Appendicular skeleton and proximal extremities are most common sites presents with pain and local tenderness; often of long duration Palpable firm mass

37 Chondrosarcoma Radiographic: Predilection for central skeleton; acetabulum or metaphysis/diaphysis of long bones Intralesional calcification classically in form or rings and arcs (65%) Cortical destruction; soft tissue extension with large lesions

38 Chondrosarcoma

39 Chondrosarcoma

40 Chondrosarcoma Binucleation and myxoid change of cartilage are helpful but not absolute indicators of malignancy Lack of osteoid (conventional)

41 Fibrous dysplasia Clinical: Often asymptomatic; incidental finding or bone growth deformity Solitary (monostotic) or multiple bones involved (polyostotic)

42 Fibrous dysplasia Radiologic: Metaphyseal or diaphyseal based lesion Lytic or ground glass appearance Bowing and pathologic fracture (shepherd's crook deformity) Cystic degeneration is common

43 Fibrous dysplasia Can be uni- or multifocal (polyostotic) Multifocal FD seen in Albright-McCune and Mazabraud s syndromes

44 Fibrous dysplasia Histopathology: Fibrous stroma of variable density; small bland spindled cells Osteoid trabeculae of unusual shapes; alphabet soup or psammoma bodies Lack of osteoid rimming Foci of cartilaginous metaplasia, lipid laden macrophages and cystic degeneration Rare multinucleated giant cells

45 This resembles a membranous growth process without fibrous rimming. Metaplastic process where osteoid forms right out of fibrous matrix. Simulates bone tumor clinically.

46 Fibroma Also known as fibrous metaphyseal defect, non-ossifying fibroma Peak incidence in adolescents and young adults May be discovered incidentally or present with pathologic fracture Metaphyseally centered lesion, lower extremity is most common location

47 Fibroma/NOF Rad: sharply demarcated, expansile lesion of the cortex; metaphyseal Lesion is parallel to long axis of affected bone

48 Fibroma/ NOF Because of pathognomonic appearance and tendency for spontaneous resolution, seldom encountered in SP

49 Bone cysts

50 Giant cell tumor Most often in skeletally mature individuals (third decade) Most common location = knee, distal radius, sacrum Pain, swelling and pathologic fracture Classically epiphyseal

51 Giant cell tumor Radiology: Epiphyseal centered; extends to articular surface lytic lesion lacking significant sclerosis or periosteal reaction Confined to bone or break through cortex into soft tissue Radiologically simulates malignancy: osteosarcoma

52 Giant cell tumor Histopathology: May have necrosis or secondary cyst formation Uniform pattern of growth with numerous giant cells Background of round /oval mononuclear cells- -same as multinucleate cells; no cytologic atypia

53 Ewings Sarcoma Clinical: Lesion of adolescents and young adults Presents with local pain and swelling; may have fever and simulate infection **Rx d with radiation and adjuvant chemotherapy t (11;22); related cytogenetically to PNET and DSRCT, Askins

54 Ewing Sarcoma Radiologic: Extensive, poorly marginated diaphyseal lesion Periosteal new bone formation and soft tissue mass May be lytic and /or sclerotic Ddx: lymphoma and osteomyelitis

55 Ewing Sarcoma Histopathology: Small round blue cell tumor Pas +/diastaseintracytoplasmic glycogen may show extensive necrosis and crush artifact

56 Chordoma Clinical: Associated with wide age range majority of lesions of sacrum or clivus pain but also nerve/spinal cord compression, change in bowel, cranial nerve dysfunction or nasopharyngeal mass

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58 Pigmented villonodular synovitis PVNS Common proliferative/neoplastic lesions of joints; progressive discomfort nodular, villous thickening of the synovium with hemosiderin deposition

59 PVNS Periarticular soft tissue swelling and mass effect Extensive bone destruction (simulating aggressive disease) can be present Hemosiderin identified on MRI

60 PVNS Large villi filled with dense infiltrate of fibrohistiocytic mononuclear cells, hemosiderin laden macrophages and giant cells. Numerous mitoses may be identified; NOT an indicator of aggressive potential

61 Soft tissue tumor/ Sarcoma Lesions of adipose tissue: Lipoma/Liposarcoma Lesions of skeletal muscle: Rhabdomysarcoma Lesions of primitive/progenitor/multipotential cell: Malignant fibrous histiocytoma (MFH) Lesion of? Tissue/cell: Synovial sarcoma

62 Lipoma

63 Liposarcoma One of the more common sarcomas Develop in the deep soft tissue; thigh and retroperitoneum Treatment is surgical; prognosis is dependent on grade, size, location

64 Liposarcoma Different variants with prognostic significance: well differentiated, myxoid/round cell and pleomorphic Histology = Lipoblasts

65 Rhabdomyosarcoma One of the more common tumors of children Occurs in unusual sites: head and neck, orbit, urogenital region

66 Rhabdomyosarcoma Key to Dx is recognition of rhabdomyoblast

67 Synovial sarcoma Commonly arises near joints/extremities Histologically biphasic t(x;18)

68 Chromosomal abnormalities in Soft tissue sarcoma

69 Malignant fibrous histiocytoma